Both campaigns declared victory as CNN and YouGov polls reported Clinton the victor and Trump's chances of getting elected barely budged in betting markets.

We could talk about the fact that nearly every word out of his mouth was untrue; that he dredged up every right-wing conspiracy theory that finds home in the conservative fever swamp; and that he had three women who have accused Bill Clinton of sexual impropriety as guests at the debate.

"OK, Donald. I know you're into big diversion tonight, anything to avoid talking about your campaign and the way it's exploding and the way Republicans are leaving you".

Trump's vice-presidential running mate, Mike Pence, was the subject of rumours that he might bolt the Trump ticket in disgust at the leaked lewd video, in which Trump made vulgar remarks about women.

"I'm honored to be standing with him", Pence said.

Trump's creepy body language was widely noticed by debate watchers. Ignore the lies; the exaggerations; the grossness of Trump calling bragging about sexual assault "locker room talk". Clinton said the "Trump effect" is showing up all over America, saying even bullying is up.

Clinton's performance inspired online criticism as well. They cheered when Trump interrupted Clinton to state the former Secretary of State would "be in jail" if he was "in charge of the law in our country".

New Hampshire Sen Kelly Ayotte, who was a top Trump supporter, said she would write-in Mr Pence as her choice for president on Election Day. He did settle a lawsuit with one of the women who claimed harassment.

"This looks like a poster for a 1970s horror movie", tweetedNew York Times culture writer Dave Itzkoff in response to a photo of Trump standing behind Clinton and frowning.